The present invention generally relates to video teleconferencing systems, and more particularly to a video teleconferencing system which provides from a server a video teleconferencing service to a plurality of terminals which are coupled via a network.
Recently, video teleconferencing systems are used popularly. According to the video teleconferencing system, a plurality of terminals are coupled via a network and console information such as characters, voice information and image information are combined and exchanged among the terminals to enable a video teleconferencing. The video teleconferencing system is advantageous in that the system frees the users from being restricted by the conference location, and for this reason, there are demands to improve the video teleconferencing system by providing smooth progress and presence.
FIG. 1 shows an essential part of an example of a conventional video teleconferencing system. In FIG. 1, only two terminals 200 are shown, and each terminal 200 includes a camera 201 and a display 202. The camera 201 is provided above the display 202, and the terminal 200 transmits image information related to the user by picking up the user on this camera 201.
However, according to this system shown in FIG. 1, it is impossible to achieve eye-to-eye contact between users A and B. In other words, in order for the user A to send a front image of himself to the user B, the user A must shift his eyes from the display 202 and look upward towards the camera 201. On the other hand, in order for the user B to see the user A, the user B must look straight at the display 202. As a result, the user B picked up by the camera 201 in this state appears on the display 202 on the side of the user A as if the user B is looking down, and there is no eye-to-eye contact between the users A and B.
FIG. 2 shows an essential part of another example of the conventional video teleconferencing system. In FIG. 2, those parts which are the same as those corresponding parts in FIG. 1 are designated by the same reference numerals, and a description thereof will be omitted. In FIG. 2, a semitransparent mirror (half mirror) 203 is provided in front of the display 202 at each terminal 200. The camera 201 is provided above the semitransparent mirror 203.
According to this system shown in FIG. 2, it is possible to realize eye-to-eye contact between the users A and B. However, if the video teleconference involves three or more people, it becomes uncertain who is requesting eye-to-eye contact to who.
Therefore, the conventional video teleconferencing systems have problems in that it is either impossible to achieve eye-to-eye contact between two users or, it is uncertain who is requesting eye-to-eye contact to who in the case where the eye-to-eye contact is possible. As a result, it is difficult to ensure smooth progress of the video teleconference and provide presence at each of the terminals.